Question

1-Calcule o sistema.

3X+2Y=16
-3X+2Y=4

X+y=10
X-Y=4

X+3Y=8
X-3Y=2

Answer 1

$x = 10 - y \\ x - y = 4 \\ \\ 10 - y - y = 4 \\ y = 3 \\ \\ x = 10 - 3 \\ x = 7 \\ (x \: y) = (7 \: 3)$
$x = 8 - 3y \\ x - 3y = 2 \\ \\ 8 - 3y - 3y = 2 \\ y = 1 \\ \\ x = 8 - 3 \times 1 \\ x = 5 \\ \\ (x \: y) = (5 \: 1)$